Electric meter.



No. 653,806. Patented July l7, I900. C. D. HASKINS.

ELECTRIC METER.

(Application filed my 8, 1899.)

(No Mndel.)

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NITED STATES PATENT DEE CE.

cARYL D. HASKINS, OF NEWTON, MASSACHUSETTS, ASSIGNOR TO THE GENERAL ELECTRIC COMPANY, OF NEW YORK.

ELECTRIC METER.

SPECIFICATION arming: art of Letters Patent Nb. 653,806, dated July 17 1906. Application filed May 8, 1899. Serial No. 715,911. (No model.)

To cbZZ whom it may concern:

Be it known that I, OARYL D. HAsKINs, a citizen'of the United States, residing at Newton, in the county of Middlesex and State'of Massachusetts, have invented certain new and useful Improvements in Electric Meters, (Case No. 979,) of which the following is a specification.

My present invention relates to electric meters, and has for its object to provide a simple and efficient method of adjusting the compensation for friction in such devices. This I am able to do without afiecting the calibration of the meter. As is well known, this compensation is now usually accomplished by providing an auxiliary shuntfield acting in the same direction as the series field. This is of high resistance and very small eifect, being designed to just balance the friction, so that the armature, when no current is being used, without actually turning is upon the very point of doing so. number of Ways of adjusting the effect of this coil have been proposed. In general it is found best to connect the coil in series with the armature, because by this the advantage of the high resistance of the armature-circuit is obtained, so that the number of turns of the minute wire required in these fields may be considerably reduced. It is manifest, however, that this connection makes the resistance of the shunt-coil a part of the total re sistance of the armature-circuit and that therefore any scheme of adjustment which contemplates varying its effect by changing the resistance or number of turns in the customary Way for altering its magneto-motive force must be defective, because it changes the calibration of the meter. It is to afford a simple and convenient means of obviating this defect that I have devised the present invention, which consists of means for varying the magneto-motive force of the shunt starting-coil with reference to the armature independent of any change in its absolute magneto-motive force. The most convenient way which I have as yet devised for doing this is by mounting the starting-coil (or a desired portion thereof) upon a pivot and adjusting its angular relation to the armature so that its inductive effect can be changed from zero to maximum, according to the di rection of the plane of the coil.

The accompanying drawings show an em} bodiment of theinvention, Figure 1 being a plan and Fig. 2 a side elevation, both partly in section, of a meter built according to the invention. Fig. 3 is an enlarged detail of the supports of the coil in side elevation at a right angle to the section shown in Fig. 2. Fig. 4 is a sectional detail showing a modification.

The circuits of the particular meter here shown will not be illustrated, because they are so well knownas to render it unnecessary. In general it may be said that the field-magnet coils B B are in series in the branch the load upon which is to. be measured, and the aroma ture A has its winding in shunt across the mains and in series with a large resistance, the e ffeot designed being that of substantiallyconstant current in the armature-circuit and the resistance being so chosen as to cut the current down to the smallest possible amount which will give satisfactory torque in order to reduce theamount of energy consumed by the meter itself.

The starting-coil is illustrated at C. It is supported upon suitable pivots in bearings A worm-wheel E is fast to the axle of the coil, and a worm d meshes With it, the Worm being carried upon the shaft D, supported in bearings d CZ, and being turned by the button D. It is obvious that the motion of the Worm will turn the coil 0 about its axis, the electrical connections being made sufliciently flexible to permit the small movement necessary, and that as it approaches the dotted-line position in Figs. 1 and 2 its effect will be cut down until its efiect upon the armature is practically mll. The mounting of the coil G and shaft D is by clamps F F F, and the coil is preferably arranged Within the space occupied by the series field-magnet coils, since that is its best position. Of course it might be placed in other positions; but this is a convenient arrangement.

In Fig. 1 I show that the entire starting coil need not be wound to be movable. Here 0' is a portion of thestarting-coil, approximately one-half of its total turns, which is assembled beside or concentric with the seaway from the armature.

ries coilB'. In this case a little different electrical action takes place, although it is still within the same principles as those already pointed out. Here of course the effect of the part C is substantially constant, and the effectof the part 0 will depend upon not only its angular relation with regard to the armature, but the direction of current in'it with reference to the coil 0. In other words, in the first arrangement referred to the effect of the coil. is from zero to maximum by rotating through ninety degrees, Whereas Where the coil is divided in the way just pointed out the rotation would need to be through one hundred and eighty degrees. When the coils oppose each other, they would have no efiect upon the armature, and the efiect may be anything desired from zero to maximum effect of both coils in multiple. The second arrangement would necessarily, on account of its greater amplitude of movement, afford more delicacy of adjustment; but in general the first is to be preferred. I regard not only the electrical actions herein described as new with me, but also the mechanical features, the supporting of the coil upon clamps which may be adjusted in position being manifestly of considerable utility in such devices.

The arrangement above outlined constitutes What I now consider the best method of practicing the invention; butit is possible to alter the relation existing between the shunt-field and the armature, so as to some extent at least accomplish the same purpose by simply shifting the field toward or This I have illustrated in Fig. at, which is a section showing the starting-coil arranged to slide on ways 9 9, so as to be brought closer to and farther from the armature, as may be desired. For some reasons this is an efficacious way of accomplishing the desired result, principally because the starting-coil might be made of less turns, being nearer to the armature (on account of the less space required for moving the coil) than when it is pivoted.

That I claim as new, and desire to secure by Letters Patent of the United States, is

1. In an electric-motor meter, the combination with the load field-coils and the armature in shunt across the mains, of a starting-coil also in shunt, and means for adjusting the relative position of the armature and starting-coil to vary the friction compensation.

2. In an electric-motor meter, the combination with the armature, the series field-coils,

and the shunt starting-coil in series with the armature, of means for adjusting the relative position of the armature and the shunt fieldcoil to adjust the friction compensation of the meter without affecting its calibration.

3. The combination with an electric-motor meter, of a rotatable startingcoil, and means for adjusting the angle at which the coil is presented to the armature.

4. The combination with a motor-meter, of a starting-coil, mounted in bearings secured by clamps upon the series field-coils, and means for rotating the starting-coil.

5. The combination with a rotatable startingcoil in a motor-meter, of gearing by which the coil may be adjusted to any desired angular position with reference to the armature.

6. The combination with a motor-meter, of a starting-coil, in addition to the ordinary motor elements, and means for varying the effect of the starting-coil independent of variation in its absolute magneto-motive force.

In witness whereof I have hereunto set my hand this 5th day of May, 1899.

CARYL D. HASKINS.

Witnesses:

BENJAMIN B. HULL, MABEL E. JAooBsoN. 

